Macrofauna and meiofauna were quantitatively sampled along 3 transects through high energy surf zones to nearshore waters. While 1 transect included some gravel patches, the other 2 exhibited increasingly finer sand and more silt and clay fraction with distance beyond the breaker zone. Meiofaunal abundance and biomass increased beyond the breakers and then decreased again further offshore. Macrofaunal abundance and diversity increased offshore; biomass increased offshore in one case while it reached a peak a little way beyond the breakers in the other. Numerical classification revealed 3 macrofaunal assemblages. The first occupied the surf zone or inner turbulent zone and included species characteristic of the sublittoral fringe of intertidal sandy beaches. The third assemblage occupied the outer turbulent zone; it started well beyond the break point and was marked by a rapid increase in biomass and diversity. The second assemblage represents a transition zone between these 2. It had no unique species but included reduced numbers of some species typical of both inner and outer turbulent zones. This transition zone, just outside the breakers, marks the region where wave energy reaching the bottom rapidly declines from its peak at the break point. A zonation scheme for the intertidal and subtidal macrofauna of high energy sandy coasts is proposed and implications of this are discussed.

Faunal mass mortalities are a sporadic, but not uncommon, feature of the West and South coasts of South Africa. Five mass mortalities of West Coast rock lobsterJasus lalandii, including three of the most severe ever recorded in South Africa, occurred in the 1990s and resulted in the stranding of about 2263 tonnes of lobster. The bulk (97%) of the loss occurred in the last three years of the decade. The five events occurred within an 80 km stretch of coastline that straddled two fishing zones and resulted from hypoxic conditions associated with highbiomass dinoflagellate blooms. In each case, the quantity of lobsters stranded was directly related to the extent or duration of low-oxygen conditions. Small females constituted the bulk of the lobster stranded in most events. The lobster fisheries in the affected fishing zones suffered severe impacts. Recovery in one zone appears to be extremely slow, whereas the other zone is more resilient. Not only would a continuation of the trend of increasing frequency and severity of lobster strandings devastate the rock-lobster fishing industry and the employment prospects of small fishing communities, but it could also seriously affect the ecology of the region.

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The biochemical composition of the hepatopancreas and abdominal muscle tissue of adult male Jasus lalandii in two size classes was examined on a monthly and moult-cycle basis over four years to determine the accumulation and utilization of the major reserves in these tissues. The possibility of using this information to predict moult increment, defined as the increase in carapace length, was examined. Two study areas were selected to provide contrasting information on high and low growth rates, and the annual moult increments in these areas were determined from tag-and-recapture studies. The biochemical composition of abdominal muscle did not meet the prerequisites for a predictive index of growth. Hepatopancreas moisture content (lowest values measured during accumulation of reserves) showed a negative correlation with growth increment. Peak lipid content (as both percentage and absolute values) showed a positive correlation with measured moult increment. The relationship between percentage of lipid (both size classes combined) and moult increment was highly significant. Notwithstanding the limitations introduced by the small number of high-growth data points in this study, it appears that hepatopancreas lipid content can be used as a simple and robust predictive indicator of growth in adult male J. lalandii.

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